The present invention relates to a roller assembly for cleaning the surface of a substrate, such as an identification card, on which information is to be printed or applied, and for removing debris that collects on a cleaning roller which contacts the substrate. The assembly includes an endless flexible band of pressure sensitive adhesive that engages a soft rubber roller used for picking debris off the substrate and which removes the collected debris from the substrate engaging roller.
A problem arises with printing ID cards that are removed from a card stack when there are bits of debris on the surface of the card. The debris may be small bits of material from trimming or cutting, or even an accumulation of lint, dust or other debris. The debris has to be removed in order to obtain high quality printing, and at the present time soft rubber rollers that have a sticky or adhesive outer surface are used. The soft rubber rollers roll over the surface of the card to pick up the debris. These cleaning rollers are well known and are defined as cleaning rollers having a sticky or low force adhesive outer surface.
However, the cleaning rollers may become contaminated quickly and lose effectiveness, as well as starting to miss some debris as the roller surface fills up. Changing the rollers whenever they do become contaminated is a time consuming job.
A printer made by Eltron International, Inc. of Simi Valley, Calif., has a card cleaning cartridge in their Model P310 printer. However, this cartridge includes a separate cleaning roller that will be used for moving material from a card, and can be removed and replaced when it becomes contaminated.
Additionally, Datacard Corporation of Minneapolis, Minn., has a card cleaning roller assembly that has a tape which will strip collected particular material away from the cleaning rollers after a predetermined number of cards have been cleaned. Spools of adhesive type tape are used for this arrangement. Such a device is shown in U.S. Pat. No. 5,401,111.
In the system, the tape that is used for removing debris is not driven by the cleaning rollers, but rather is driven to remove the tape at periodic intervals under a positive drive.
The present invention relates to a cleaning assembly for removing debris from the surface a card cleaning roller in a printing operation. A soft cleaning roller engages the surface of the card to be printed as is known. The cleaning roller has a sticky surface that will pick up debris from the card. An endless band or belt of substantial surface area which has a pressure sensitive adhesive on an outer surface engages the sticky surface cleaning roller on the side of the cleaning roller opposite from the card, so that any debris that adheres to the surface of the cleaning roller is removed by the pressure sensitive adhesive on the band or belt. The pressure sensitive adhesive on the endless band surface is a higher force adhesive than the cleaning roller surface. The belt has a substantial surface area so that it can be used for a length of time without changing, to thereby reduce the costs of removing debris from cards to be printed.
The belt and cleaning roller preferably are contained in a cartridge that carries the cleaning roller that runs against a card surface. A pair of tape mounting rollers that are spaced apart are supported on the cartridges. The tape mounting rollers support the belt of adhesive material. One of the tape mounting rollers is supported so the endless band of material is urged against the surface of the sticky cleaning roller. The endless band or belt having the adhesive surface will be driven to move by the cleaning roller as the sticky surface cleaning roller rotates from movement of the card it is engaging. When the endless band of adhesive surface material or tape is full of debris, the cartridge can be removed, and the endless band replaced with new band easily.
The cleaning assembly is reliable, easily used and reduces down time for servicing the cleaning rollers.